1. Field of the Invention
The present invention relates to a camera module and a method of manufacturing the same.
2. Description of the Related Art
Recently, camera modules are mounted on IT devices such as mobile terminals, PDAs (Personal Digital Assistant), MP3 players and so on. With the development of technology, the resolution of the camera modules changes from 300,000 pixels (VGA) to several million pixels, and the reduction in size and thickness of the camera modules are being performed depending on mounting targets. Further, the camera module provides various additional functions, such as auto-focusing (AF) and optical zoom.
In general, a compact camera module (CCM) has a small size and is applied to various IT devices such as camera phones, PDAs, and smart phones. Recently, more and more devices having a small-sized camera module mounted thereon have been launched on the market in accordance with consumers' tastes.
Such a camera module is manufactured using a charge coupled device (CCD) or complementary metal oxide semiconductor (CMOS) image sensor as a main component. Incident light transmitted through the lens is condensed by the image sensor and is stored as data in a memory. The stored data is displayed as an image through a display medium, such as liquid crystal display (LCD) or PC monitor.
Typical camera modules are manufactured by a chip-on-film (COF) method, a chip-on-board (COB) method, and a chip scale package (CSP) method, among which the COF method and the COB method are widely used.
Recently, a wafer-level camera module (WLCM) which can be mass-produced has been proposed, in order to maximize a price reduction.
The WLCM can be mass-produced because an image sensor and a lens are manufactured by a wafer level method. Further, since the WLCM can be directly mounted on a main substrate, it is possible to reduce the price of a mobile phone having the WLCM mounted therein.
To manufacture a conventional WLCM, a lens wafer is attached to a wafer having image sensors formed thereon through a bonding method. Thereafter, the wafer having the lens wafer attached thereto is diced into a plurality of unit modules. Then, an optical case of which only an incident port is opened is coupled to each of the unit modules, thereby completely manufacturing a WLCM.
At this time, to couple the optical case to the unit module, a series of processes of rearranging the optical case, applying bond, attaching the case, and curing the module should be accompanied. Therefore, the manufacturing cost may increase.
Further, when the WLCM is affected by electrostatic discharge (ESD) or electromagnetic waves caused by a mobile terminal having the WLCM mounted thereon or an electrical effect from the outside of the mobile terminal, the WLCM may malfunction or image noise may occur.
Therefore, although the WLCM has been proposed to reduce a cost, there is a limit in reducing the manufacturing cost of the WLCM, because the manufacturing process of the WLCM is complex. Further, defects may occur due to ESD or electromagnetic waves.